Radiographic Features of the Metacarpal in Blauth Type III Thumb Hypoplasia.

PURPOSE: The purpose of this study was to investigate whether radiographs can be used to aid in the determination of Blauth IIIA and IIIB thumbs. METHODS: Six pediatric hand surgeons were asked to evaluate the radiographs of 77 thumbs and classify the thumb as IIIA or IIIB and indicate which morphologic features influenced their decision. Quantitative measurements and ratios of radiographs were obtained and compared between IIIA and IIIB thumbs. RESULTS: The radiographic features selected for type IIIA thumbs include near-normal length and near-normal width and for type IIIB thumbs, abnormally short, tapered proximal end, and round proximal end. The six surveyed surgeons reached consensus in 82% (63/77) of thumbs, and this matched the enrolling surgeon's classification in 77% (59/77) cases. The ratio of the length of the thumb metacarpal compared with the length of the index metacarpal was different between IIIA and IIIB thumbs (66% ± 0.08% and 46% ± 0.18%, respectively). The ratio of the width of the thumb metacarpal shaft at its narrowest aspect to the width of the thumb metacarpal base was notably different between IIIA and IIIB (68% ± 0.13% and 95% ± 0.28%, respectively). CONCLUSIONS: Near-normal length and near-normal width of the metacarpal were used to predict IIIA and abnormally short, abnormally narrow, and a round or tapered base of the metacarpal were used to predict IIIB classification. The length of the thumb metacarpal relative to the index metacarpal is on average 66% of the length of the index metacarpal in IIIA thumbs compared with 46% in IIIB thumbs. The width of the shaft of the thumb metacarpal at its narrowest is 68% of the width of the thumb metacarpal base in IIIA thumbs, indicating a flared base. In IIIB thumbs, the shaft width was on average 95% of the base width, indicating a tapered base. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic level III.

Antegrade femoral lengthening and simultaneous hemiepiphysiodesis for congenital femoral deficiency.

Purpose: Congenital femoral deficiency is characterized by limb length discrepancy and genu valgum. Lengthening of the femur along its anatomic axis increases valgus alignment by medial knee translation. Pairing limb lengthening with simultaneous medial distal femoral hemiepiphysiodesis can simultaneously correct two limb deformities. Methods: All skeletally immature patients with congenital femoral deficiency who underwent antegrade femoral lengthening and concomitant guided growth over a 4-year period were reviewed. Length and alignment data were quantified during lengthening, consolidation, and for 1 year after guided growth implants were removed or the patient reached skeletal maturity. Digital simulation was performed for all lengthenings to assess the mechanical alignment that would have been achieved had lengthening been performed without medial distal femoral hemiepiphysiodesis. Results: Nine patients (five males, four females, mean age = 12.3 ± 1.9 years) underwent 10 antegrade intramedullary femoral lengthenings with simultaneous medial distal femoral hemiepiphysiodesis. All had improvement in valgus alignment (average improvement in mechanical axis deviation was 18 ± 11 mm, average change in limb alignment was 6 ± 5°). In simulated lengthenings without guided growth, all limbs would have experienced increased lateral mechanical axis deviation of 5 ± 3 mm. The hemiepiphysiodesis implant and lengthening device were explanted simultaneously in 7 of 10 lengthenings. Conclusion: Simultaneous medial distal femoral hemiepiphysiodesis with antegrade femoral lengthening for ongenital femoral deficiency can minimize the number of surgical episodes for the skeletally immature patient. The lengthening device and guided growth construct can be removed simultaneously in a majority of cases, saving children one or two additional surgical treatments.

Predictors of Persistent Limp Following Proximal Femoral Varus Osteotomy for Perthes Disease.

INTRODUCTION: One of the most popular containment procedures for Legg-Calvé-Perthes disease (LCPD) is proximal femur varus osteotomy (PFO). While generally successful in achieving containment, PFO can cause limb length discrepancy, abductor weakness, and (of most concern for families) a persistent limp. While many studies have focused on radiographic outcomes following containment surgery, none have analyzed predictors of this persistent limp. The aim of this study was to determine clinical, radiographic, and surgical risk factors for persistent limp 2 years after PFO in children with LCPD. METHODS: A retrospective review of a prospectively collected multicenter database was conducted for patients aged 6 to 11 years at disease onset with unilateral early-stage LCPD (Waldenström I) who underwent PFO. Limp status (no, mild, and severe), age, BMI, and pain scores were obtained at initial presentation, 3-month, and 2-year postoperative visits. Preoperative and follow-up radiographs were used to measure traditional morphologic hip metrics including acetabular index (AI), lateral center-edge angle (LCEA), and femoral neck-shaft angle (NSA). Univariate analysis as well as multivariate logistic regression models were used to analyze factors associated with mild and severe limp at the 2-year visit. RESULTS: A total of 95 patients met the inclusion criteria, and of these 50 patients underwent concomitant greater trochanter apophysiodesis (GTA) at the time of PFO. At the 2-year visit, there were 38 patients (40%) with a mild or severe limp. Multivariate logistic regression revealed no significant radiographic factors associated with a persistent limp. However, lower 2-year BMI and undergoing GTA were associated with decreased rates of persistent limp regardless of age (P<0.05). When stratifying by age of disease onset, apophysiodesis appeared to be protective against any severity of limp in patients aged 6 to 8 years old (P= 0.03), but not in patients 8 years or older (P= 0.49). CONCLUSIONS: Persistent limp following PFO is a frustrating problem that was seen in 40% of patients at 2 years. However, lower follow-up BMI and performing a greater trochanter apophysiodesis, particularly in patients younger than 8 years of age, correlated with a lower risk of postoperative limp.

Do Weightbearing Restrictions Cause Excess Weight Gain in Children With LEGG-Calvé-Perthes Disease?

BACKGROUND: Restricted weight bearing is commonly prescribed in Legg-Calvé-Perthes Disease (LCPD), raising concerns of causing overweight or obesity. This study utilizes prospectively collected data to address the following questions: (1) does body mass index (BMI) Z-score increase over the course of LCPD follow-up; (2) is having a BMI category of normal, overweight, or obese at baseline associated with BMI Z-score changes over the course of follow-up; and (3) is the duration of weight bearing restrictions (no restrictions, <3, 3 to <6, 6 to 9, or >9 mo) associated with BMI Z-score changes. METHODS: Data of 130 children aged 5 to 12 years with unilateral early-stage LCPD were extracted from an international database. Nation-specific BMI Z-scores and percentile-based weight categories were determined, and the duration of follow-up and weight bearing restrictions were calculated. Longitudinal changes in BMI Z-scores were evaluated for the 3 study questions using mixed effects linear regression models with surgery as a covariate. Sensitivity analyses were used to determine the influence of socio-cultural background (USA vs. India) for each study question. RESULTS: During the 35.5±15.9 months of follow-up, no statistically significant increase in BMI Z-scores was observed across the entire cohort, or following stratification by baseline weight categories or the duration of the weight bearing restriction. Sensitivity analyses indicated that patients in the USA had no change in their BMI Z-score. When stratified by weight categories, the normal weight of US children had a small increase in their BMI Z-score (0.005 per mo, 95% confidence interval: 0.0002, 0.009), but this was not seen in other BMI categories. The cohort of Indian children had a small but significant decrease in their BMI Z-score (-0.005/mo, 95% CI: -0.009, -0.0002). After stratification by weight categories, a small decrease of the BMI Z-score was observed only in the Indian overweight children (-0.016 per mo, 95% CI: -0.027, -0.005) and no other BMI category. CONCLUSIONS: Weightbearing restrictions over the course of follow-up for our cohort of children with early-stage LCPD were not associated with clinically meaningful increases of BMI Z-scores. Weight gain is multi-factorial and probably not caused by weight bearing restrictions alone. LEVEL OF EVIDENCE: III Diagnostic Study.

Complications in the 2-Year Postoperative Period Following Pediatric Syndactyly Release.

PURPOSE: Syndactyly surgical release is one of the most common congenital hand surgeries performed by pediatric hand surgeons. The purpose of our study was to evaluate the complications associated with syndactyly release and determine factors that correlate with higher complication rates within the 2-year postoperative period. METHODS: A retrospective chart review was completed for patients who underwent syndactyly release at a single pediatric center between 2005 and 2018. Patients were included if they had a diagnosis of syndactyly and underwent surgical release, and excluded for a diagnosis of cleft hand, incomplete surgical documentation, surgery performed at an outside institution, or follow-up care that did not extend beyond the first postoperative visit. Complications were classified using the Clavien-Dindo (CD) system. RESULTS: Fifty-nine patients met the inclusion criteria, which included 143 webs released in 85 surgeries. A total of 27 complications occurred for the 85 surgeries performed. The severity of complications was CD grade I or II in 23% of surgeries, most commonly unplanned cast changes, and CD grade III in 8% of surgeries. No CD grade IV or V complications occurred. The CD grade III complications included 6 reoperations. The complication rate was higher when performing >1 syndactyly release per surgery. It also was higher for patients undergoing >1 surgical event. Rates of complication per surgery were similar between patients with multiple surgeries compared with those with a single surgery. Concomitant diagnoses and complexity of syndactyly was not associated with a higher complication rate. CONCLUSIONS: Syndactyly release was associated with a complication rate of 31% per surgical event with 44% of these complications related to unplanned cast changes and 8% of complications that required admission or reoperation. Risk factors for complications following syndactyly release include >1web operated on per surgery and undergoing >1 surgical event. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognosis IV.

Intraoperative Neurological Monitoring in Lower Limb Surgery for Patients With Mucopolysaccharidoses.

BACKGROUND: There are reports of spinal cord injury (SCI) occurring after lower extremity (LE) surgery in children with mucopolysaccharidoses (MPS). Intraoperative neurological monitoring (IONM) has been adopted in some centers to assess real-time spinal cord function during these procedures. The aim of this investigation was to review 3 specialty centers' experiences with MPS patients undergoing LE surgery. We report how IONM affected care and the details of spinal cord injuries in these patients. METHODS: All pediatric MPS patients who underwent LE surgery between 2001 and 2018 were reviewed at 3 children's orthopaedic specialty centers. Demographic and surgical details were reviewed. Estimated blood loss (EBL), surgical time, positioning, use of IONM, and changes in management as a result of IONM were recorded. Details of any spinal cord injuries were examined in detail. RESULTS: During the study period, 92 patients with MPS underwent 252 LE surgeries. IONM was used in 83 of 252 (32.9%) surgeries, and intraoperative care was altered in 17 of 83 (20.5%) cases, including serial repositioning (n=7), aggressive blood pressure management (n=6), and abortion of procedures (n=8). IONM was utilized in cases with larger EBL (279 vs. 130 mL) and longer operative time (274 vs. 175 min) compared with procedures without IONM. Three patients without IONM sustained complete thoracic SCI postoperatively, all from cord infarction in the upper thoracic region. These 3 cases were characterized by long surgical time (328±41 min) and substantial EBL (533±416 mL or 30.5% of total blood volume; range, 11% to 50%). No LE surgeries accompanied by IONM experienced SCI. CONCLUSIONS: Patients with MPS undergoing LE orthopaedic surgery may be at risk for SCI, particularly if the procedures are long or are expected to have large EBL. One hypothesis for the etiology of SCI in this setting is hypoperfusion of the upper thoracic spinal cord due to prolonged intraoperative or postoperative hypotension. IONM during these procedures may mitigate the risk of SCI by identifying real-time changes in spinal cord function during surgery, inciting a change in the surgical plan. LEVEL OF EVIDENCE: Level III-retrospective comparative series.

Tissue selective effects of bazedoxifene on the musculoskeletal system in female mice.

The actions of selective estrogen receptor modulators are tissue dependent. The primary objective of the current study was to determine the tissue selective effects of bazedoxifene (BZA) on the musculoskeletal system of ovariectomized (OVX) female mice, focusing on the strengths of muscle-bone pairs in the lower hindlimb. Treatment with BZA after ovariectomy (OVX+BZA) did not prevent body or fat mass gains (P < 0.05). In vivo plantarflexor muscle isometric torque was not affected by treatment with BZA (P = 0.522). Soleus muscle peak isometric, concentric and eccentric tetanic force production were greater in OVX+BZA mice compared to OVX+E2 mice (P ≤ 0.048) with no effect on maximal isometric specific force (P = 0.228). Tibia from OVX+BZA mice had greater cortical cross-sectional area and moment of inertia than OVX mice treated with placebo (P < 0.001), but there was no impact of BZA treatment on cortical bone mineral density, cortical thickness, tibial bone ultimate load or stiffness (P ≥ 0.086). Overall, these results indicate that BZA may be an estrogen receptor agonist in skeletal muscle, as it has previously been shown in bone, providing minor benefits to the musculoskeletal system.

Demographics and Clinical Presentation of Early-Stage Legg-Calvé-Perthes Disease: A Prospective, Multicenter, International Study.

BACKGROUND: Children with Legg-Calvé-Perthes disease (LCPD) are classically described as small, thin, high-energy children presenting with a painless limp. Epidemiologic studies have historically been retrospective and regional in nature. The purpose of this study was to determine the demographic and clinical features of children presenting in the early stages of LCPD in an international, multicenter cohort. METHODS: Children (6 to 10 years) in the early stages of LCPD (modified Waldenström stage I to IIa) were enrolled in a prospective, multicenter study. Demographic and clinical data at presentation were analyzed. Body mass index percentiles were determined using country-specific growth charts for children in the United States and India, two countries with largest enrollment. Statistical analyses included t-tests and chi-square. RESULTS: A total of 209 children (86% males; mean age 7.9 ± 1.2 years) from 25 centers (six countries) were included. Eight-four percent of children presented with pain with or without a limp. Average pain score at presentation was 3 ± 2 (range 0 to 9), and 63% of children (n = 105) used pain medications. Of these children 65% required medication more than once per week. Thirty percent of children missed school due to pain in the past month, and of those, 74% missed at least 1 day per week. Twenty-nine percent of children from the United States and 20% of children from India were overweight or obese. Nineteen percent reported household smoking. DISCUSSION: This prospective study provides a new international multicenter representation of early LCPD. The frequency of pain and missed school highlights the substantial morbidity and potential social cost and burden for children and families. The prevalence of being overweight/obese in our LCPD cohort was comparable to rates within the pediatric cohort as a whole, and fewer children have a history of smoke exposure than in previous reports. LEVEL OF EVIDENCE: Level II, prospective comparative study.

A Comparative Analysis of 150 Thumb Polydactyly Cases from the CoULD Registry Using the Wassel-Flatt, Rotterdam, and Chung Classifications.

PURPOSE: Three commonly used classifications for thumb polydactyly are the Wassel-Flatt, Rotterdam, and Chung. The ideal classification system would have high validity and reliability and be descriptive of the thumb anomaly. The purposes of this investigation were to (1) compare the inter- and intrarater reliability of these 3 classifications when applied to a large sample of patients enrolled in the Congenital Upper Limb Differences (CoULD) Registry and (2) determine the prevalence of radial polydactyly types when using the various classifications in a North American population. METHODS: Inter- and intrarater reliability were determined using 150 cases of radial polydactyly presented in a Web-based format to 7 raters in 3 rounds, a preliminary training round and 2 observation rounds. Raters classified each case according to the Wassel-Flatt, Rotterdam, and Chung classifications. Inter- and intrarater reliability were evaluated with the intraclass correlation coefficient (ICC) calculated using 2-way random measures with perfect agreement. RESULTS: For Wassel-Flatt, both the interrater (ICC, 0.93) and the intrarater reliability (ICC, 0.91) were excellent. The Rotterdam classification had excellent reliability for both interrater reliability (ICC, 0.98) and intrarater reliability (ICC, 0.94), when considering type alone. Interrater analysis of the additional subtypes demonstrated a wide range of reliabilities. The Chung classification had good interrater (ICC, 0.88) and intrarater reliability (ICC, 0.77). Within the Wassel-Flatt classification, the most frequent unclassifiable thumb was a type IV hypoplastic thumb as classified by the Rotterdam classification. CONCLUSIONS: The Wassel-Flatt and Rotterdam classifications for radial polydactyly have excellent inter- and intrarater reliability. Despite its simplicity, the Chung classification was less reliable in comparison. The Chung and Rotterdam classification systems capture the hypoplastic subtypes that are unclassifiable in the Wassel-Flatt system. Addition of the hypoplastic subtype to the Wassel-Flatt classification (eg, Wassel-Flatt type IVh) would maintain the highest reliability and classify over 90% of thumbs deemed unclassifiable in the Wassel-Flatt system. CLINICAL RELEVANCE: The Wassel-Flatt and Rotterdam classifications have excellent inter-and intrarater reliability for the hand surgeon treating thumb polydactyly. Addition of a hypoplastic subtype to the Wassel-Flatt (Type 4h) allows classification of most previously unclassifiable thumbs.

Reliability of the modified lateral pillar classification for Legg Calvé Perthes disease performed by a large group of international paediatric orthopaedic surgeons.

PURPOSE: The modified lateral pillar classification (mLPC) is used for prognostication in the fragmentation stage of Legg Calvé Perthes disease. Previous reliability assessments of mLPC range from fair to good agreement when evaluated by a small number of observers with pre-selected radiographs. The purpose of this study was to determine the inter-observer and intra-observer reliability of mLPC performed by a group of international paediatric orthopaedic surgeons. Surgeons self-selected the radiograph for mLPC assessment, as would be done clinically. METHODS: In total, 40 Perthes cases with serial radiographs were selected. For each case, 26 surgeons independently selected a radiograph and assigned mLPC and 21 raters re-evaluated the same 40 cases to establish intra-observer reliability. Rater performance was determined through surgeon consensus using the mode mLPC as 'gold standard'. Inter-observer and intra-observer reliability data were analysed using weighted kappa statistics. RESULTS: The weighted kappa for inter-observer correlation for mLPC was 0.64 (95% confidence interval: 0.55 to 0.74) and was 0.82 (range: 0.35 to 0.99) for intra-observer correlation. Individual surgeon's overall performance varied from 48% to 88% agreement. Surgeon mLPC performance was not influenced by years of experience (p = 0.51). Radiograph selection did not influence gold standard assignment of mLPC. There was greater agreement on cases of mild B hips and severe C hips. CONCLUSIONS: mLPC has low good inter-observer agreement when performed by a large number of surgeons with varied experience. Surgeons frequently chose different radiographs, with no impact on mLPC agreement. Further refinement is needed to help differentiate hips on the border of group B and C. LEVEL OF EVIDENCE: III.

Distal Tibial Guided Growth for Anterolateral Bowing of the Tibia: Fracture May Be Prevented.

BACKGROUND: Congenital pseudarthrosis of the tibia is a rare and challenging pediatric condition. The pre-fracture state, called congenital tibial dysplasia or anterolateral bowing of the tibia, presents a high fracture risk due to underlying bowing and dysplasia. After fracture, there is a substantial risk of nonunion. Any union achieved may be complicated by refracture, deformity, leg-length discrepancy, stiffness, pain, and dysfunction. We present the results of using distal tibial growth modulation to improve tibial alignment and to decrease fracture risk in this condition. To our knowledge, this is the first report of isolated distal tibial growth modulation as the primary surgical treatment for this condition. METHODS: This is a retrospective study of 10 patients with congenital tibial dysplasia who presented prior to pseudarthrosis and underwent distal tibial growth modulation as a primary treatment. The medical records and radiographs were reviewed for age at the times of diagnosis and treatment, fracture, secondary procedures, complications, residual deformity, cystic changes, and leg-length discrepancy. RESULTS: Ten patients had a mean follow-up (and standard deviation) of 5.1 ± 1.9 years. No patient sustained a tibial fracture, and no patient developed a tibial pseudarthrosis after guided growth was initiated. The mean age at the initiation of growth modulation was 2.6 ± 1.3 years. Six patients required a plate exchange. The mean residual tibial diaphyseal angular deformity at the most recent follow-up was 4.3° ± 3.2° of varus and 8.4° ± 5.8° in the sagittal plane. Only 1 patient had a clinically important leg-length discrepancy, with the affected leg being longer. CONCLUSIONS: In this series of 10 patients with congenital tibial dysplasia, distal tibial growth modulation delayed or possibly prevented fracture, decreased tibial malalignment, improved radiographic appearance of bone quality, and preserved leg length. No patient developed tibial fracture or pseudarthrosis after the initiation of guided growth treatment. Although early results are promising, follow-up to maturity is required to define the exact role of this simple outpatient procedure in congenital tibial dysplasia. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Extramedullary Motorized Lengthening of the Femur in Young Children.

BACKGROUND: Limb lengthening by distraction osteogenesis is now achievable via motorized intramedullary devices, mitigating many complications of lengthening by external fixation. In young patients, antegrade intramedullary nailing of the femur risks avascular necrosis of the femoral head. A method of extramedullary placement of a motorized expandable intramedullary nail has been employed by the senior author to safely achieve femoral lengthening without the use of an external fixator in young patients. METHODS: Eleven skeletally immature patients with lower limb length discrepancy were reviewed who underwent extramedullary placement of a magnetic, expandable intramedullary nail for lengthening of the femur. Surgical details, lengthening parameters, and complications were reviewed and classified according to the modified Clavien-Dindo Classification. RESULTS: Average lengthening was 32.3 mm (range: 27 to 40 mm) comprising an average 14.8% of femoral segment length. The average lengthening duration was 6.3 weeks, and average full weight-bearing began at 12.6 weeks. All but 1 patient underwent early removal of the device at an average of 4.5 months, and 5 had immediate plating of the femur. Complications rates were comparable to other methods of femoral lengthening, including varus or procurvatum through the regenerate, and unplanned reoperation in 3 of 11 cases. Preoperative considerations included careful planning of implant length due to short femoral segments and protection of the knee joint from contracture or iatrogenic instability. CONCLUSIONS: Extramedullary placement of a magnetic expandable intramedullary lengthening nail can achieve lengthening of the femur without the use of external fixation. Considerations with this technique include careful planning of implant length relative to trochanteric-physeal distance, protection against knee subluxation during lengthening, and mitigating deformity of the regenerate. Off-label, extramedullary use of these devices can be considered to decrease the burdens of external fixation in young children. The technique begs the advent of future all-internal technology specifically designed for safe limb lengthening in this age group. LEVEL OF EVIDENCE: Level IV-retrospective case series.

A Comparison of Hip Spica Casting to Short Leg Casts and Bar after Hip Reconstruction in Cerebral Palsy.

Background Immobilization after hip reconstruction in children with cerebral palsy varies according to surgeon preference. The effect of postoperative immobilization on postoperative pain is unknown. Success in achieving hip stability and complications may also differ depending on the immobilization technique utilized. Questions/purposes Using retrospective data, we aimed to evaluate: (a) what effect does postoperative immobilization with hip spica casting versus short leg casts and bar (SLCaB); have on pain and pain management in children with quadriplegic cerebral palsy undergoing femoral and/or pelvic osteotomy? and (b) Do complications and radiographic outcomes differ between those treated postoperatively with hip spica casting and those in short leg casts? Materials and Methods Children with quadriplegic cerebral palsy (GMFCS IV-V, mean age 7.8 years [range: 3-15 years]) undergoing femoral or pelvic osteotomy between 2012 and 2014 in the treatment of spastic hip subluxation were reviewed. Modes of immobilization were compared, between spica casting (n=15) and SLCaB (n=12). Preoperative, perioperative, and postoperative pain was quantified between groups. In-hospital epidural dosage, morphine equivalent dosages (MED), adjunctive medications, early maintenance of radiographic hip stability, and all complications were noted and analyzed. Results Children were more likely to have spica cast immobilization if they were younger. Postoperative pain scores were similar between groups, with comparable patterns of epidural and MED administered during hospitalization. Spica casts were often flared up during hospitalization, but skin ulcers were uncommon and comparable between the two groups. Within 12 months of surgery, more ipsilateral femur fractures were observed distant to implants in the hip spica group, although the incidence of fractures did not meet statistical thresholds. Conclusion Spica casting and SLCaB after neuromuscular hip reconstruction did not show a difference in hip stability, narcotic pain medication usage or complication profile.

Should Proximal Femoral Implants be Removed Prophylactically or Reactively in Children With Cerebral Palsy?

BACKGROUND: Implants are commonly used to stabilize proximal femoral osteotomies in children with cerebral palsy (CP). Removal of implants is common practice and believed to avoid infection, fracture, or pain that might be associated with retained hardware. There is little evidence to support a prophylactic strategy over a reactive approach based on symptoms. The aim of this study was to compare the outcomes of prophylactic and reactive approaches to removal of proximal femoral implants in children with CP. METHODS: An intention-to-treat model was used to compare 2 institutions that followed a prophylactic (within ∼1 y) and reactive (following complication/symptoms) approach to hardware removal, respectively. Patients with CP who had femoral implants placed at or before age 16, and had ≥2-year postsurgical follow-up were included. Demographics, surgical details, reasons for removal, and complications were recorded. χ and t tests were used. RESULTS: Six hundred twenty-one patients (prophylactic=302, reactive=319) were followed for an average of 6 years (range, 2 to 17 y). Two hundred eighty-seven (95%) implants were removed in the prophylactic group at 1.2 years. In the reactive group, 64 (20%) implants were removed at an average of 4.2 years. Reasons for removal included pain; infection; fracture; or for repeat reconstruction. The rate of unplanned removals due to fracture or infection was higher in the reactive group (4.7% vs. 0.7%, P=0.002), but there was no difference in the rate of complications during/after removal between the 2 groups (1.7% vs. 3.1%; P=0.616). No specific risk factor associated with unplanned removal could be identified; but children under 8 years old seemed more likely to undergo later removal (odds ratio 1.98; 95% confidence interval, 0.99-3.99). CONCLUSIONS: Eighty percent of patients in the reactive removal strategy avoided surgery. This group did have a 4% higher rate of fracture or infection necessitating unplanned removal but these were successfully treated at time of removal with no difference in complication rates associated with removal between both groups. One would need to remove implants from 25 patients to avoid 1 additional complication, providing some support for a reactive approach to removal of proximal femoral implants in this population. LEVEL OF EVIDENCE: Level III-therapeutic.

A moderate oestradiol level enhances neutrophil number and activity in muscle after traumatic injury but strength recovery is accelerated.

KEY POINTS: The female hormone oestrogen may protect muscle from injury by reducing inflammation but this is debatable. In this study, the inflammatory response of injured muscle from oestrogen-replete mice was comprehensively compared to that from oestrogen-deficient mice. We show that oestrogen markedly promotes movement of neutrophils, an inflammatory white blood cell type, into muscle over the first few days after injury but has only a minor effect on the movement of macrophages, another inflammatory cell type. Despite the enhancement of inflammation by oestrogen in injured muscle, we found strength in oestrogen-replete mice to recover faster and to a greater extent than it does in oestrogen-deficient mice. Our study and others indicate that lower doses of oestrogen, such as that used in our study, may affect muscle inflammation and injury differently from higher doses. ABSTRACT: Oestrogen has been shown to protect against skeletal muscle injury and a reduced inflammatory response has been suggested as a possible protective mechanism. There are, however, dissenting reports. Our objective was to conduct an unbiased, comprehensive study of the effect of oestradiol on the inflammatory response following muscle injury. Female C57BL6/J mice were ovariectomized and supplemented with and without oestradiol. Tibialis anterior muscles were freeze injured and studied primarily at 1-4 days post-injury. Oestradiol supplementation increased injured muscle gene expression of neutrophil chemoattractants (Cxcl1 and Cxcl5) and to a lesser extent that of monocyte/macrophage chemoattractants (Ccl2 and Spp1). Oestradiol markedly increased gene expression of the neutrophil cell surface marker (Ly6g) but had less consistent effects on the monocyte/macrophage cell surface markers (Cd68, Cd163 and Cd206). These results were confirmed at the protein level by immunoblot with oestradiol increasing LY6G/C content and having no significant effect on CD163 content. These findings were confirmed with fluorescence-activated cell sorting counts of neutrophils and macrophages in injured muscles; oestradiol increased the proportion of CD45+ cells that were neutrophils (LY6G+ ) but not the proportion that were macrophages (CD68+ or CD206+ ). Physiological impact of the oestradiol-enhanced neutrophil response was assessed by strength measurements. There was no significant difference in strength between oestradiol-supplemented and -unsupplemented mice until 2 weeks post-injury; strength was 13-24% greater in supplemented mice at 2-6 weeks post-injury. In conclusion, a moderate level of oestradiol supplementation enhances neutrophil infiltration in injured muscle and this is associated with a beneficial effect on strength recovery.

Role of Advanced Imaging in the Diagnosis and Management of Active Legg-Calvé-Perthes Disease.

Since the first description of Legg-Calvé-Perthes disease a century ago, the diagnosis, staging, prognosis, and treatment decisions have been based on plain radiographs. The goal of treatment is prevention of femoral head deformity, yet radiographic prognostic classifications are applied in the fragmentation stage, often after deformity occurs. These classifications are assigned too late in the progression of the disease to maximize the effects of intervention. Thus, alternative mechanisms to determine femoral head involvement earlier in the disease course are warranted. Increasingly, MRI has been used in the study of the disease. Gadolinium-enhanced and diffusion-weighted MRI has shown promising results that correlate with radiographic classifications and the early radiographic outcome. Advanced imaging has improved the assessment of hinge abduction, yet the exact definition remains controversial. The role of imaging in the management of Legg-Calvé-Perthes disease is rapidly evolving. New or refined imaging techniques may eventually allow earlier prognosis and treatment.

Anteverting Bernese periacetabular osteotomy in the treatment of neurogenic hip dysplasia in cerebral palsy.

All patients with hypertonic cerebral palsy undergoing Bernese periacetabular osteotomy (PAO) between 2005 and 2014 were reviewed. Clinical and radiographic parameters, including the cerebral palsy hip classification and anterior and posterior wall indices were collected to assess acetabular reorientation. Twenty (83%) of 24 procedures involved the correction of posterolateral acetabular insufficiency and were 'anteverting PAOs'. All 20 experienced improvements in radiographic indices. Eleven (58%) of 19 PAOs in ambulatory patients were performed in the setting of other multilevel orthopedic surgery. The anteverting PAO is successful in correcting the posterolateral acetabular insufficiency present in spastic hip dysplasia, and can be performed in conjunction with a single-event multilevel surgery.

Does Intrathecal Baclofen Therapy Increase Prevalence and/or Progression of Neuromuscular Scoliosis?

STUDY DESIGN: Retrospective, case-matched review. OBJECTIVES: Compare a group of individuals with cerebral palsy (CP) who had intrathecal baclofen (ITB) pumps to a group of individuals with CP who did not have ITB pumps in order to determine if there was a difference in the prevalence of new-onset neuromuscular scoliosis, an increased rate of progression of preexisting neuromuscular scoliosis, or an increased rate of posterior spine fusion surgery in skeletally immature individuals with CP who had ITB pumps. SUMMARY OF BACKGROUND DATA: Various authors report conflicting findings, with some reporting an increased incidence or prevalence of scoliosis in individuals with CP who have ITB pumps whereas others report no difference in the rate of scoliosis between groups. METHODS: Retrospective chart and radiographic case-matched study in which individuals were matched by gender and Gross Motor Function Classification Scale (GMFCS) level. RESULTS: We found no difference in the rates of new-onset neuromuscular scoliosis for those with CP and ITB pumps and those without ITB pumps. However, we did see a higher rate of progression as well as an increased rate of posterior spine fusion surgery in individuals with CP who had ITB pumps than for those with CP who did not have an ITB pump. CONCLUSIONS: We continue to recommend ITB pump therapy for individuals with severe spasticity associated with CP (GMFCS IV and V). There is a significant risk of complications for individuals in general. The risk of neuromuscular scoliosis is relatively high in this population. Our findings suggest that individuals with CP who have ITB pumps and who do or do not have preexisting scoliosis should be monitored closely for either developing new neuromuscular scoliosis or progression of preexisting scoliosis.

Aging and the muscle-bone relationship.

Aging-induced declines in muscle size and quality are thought to contribute to catabolic alterations in bone, but changes in bone with age also profoundly alter its response to muscle-derived stimuli. This review provides an overview of some of the alterations that occur in muscle and bone with aging, and discusses the cellular and molecular mechanisms that may impact these age-associated changes.

Influence of ovarian hormones on strength loss in healthy and dystrophic female mice.

PURPOSE: The primary objective of this study was to determine whether strength loss and recovery after eccentric contractions are impaired in healthy and dystrophic female mice with low levels of ovarian hormones. METHODS: Female C57BL/6 (wild-type) or mdx mice were randomly assigned to ovarian-intact (Sham) and ovariectomized (Ovx) groups. Anterior crural muscles were tested for susceptibility to injury from 150 or 50 eccentric contractions in wild-type and mdx mice, respectively. An additional experiment challenged mdx mice with a 2-wk treadmill running protocol followed by an eccentric contraction injury to posterior crural muscles. Functional recovery from injury was evaluated in wild-type mice by measuring isometric torque 3, 7, 14, or 21 d after injury. RESULTS: Ovarian hormone deficiency in wild-type mice did not affect susceptibility to injury because the ∼50% isometric torque loss after eccentric contractions did not differ between Sham and Ovx mice (P = 0.121). Similarly, in mdx mice, hormone deficiency did not affect the percent of preinjury isometric torque lost by anterior crural muscles after eccentric contractions (P = 0.952), but the percent of preinjury torque in posterior crural muscles was lower in Ovx than in Sham mice (P = 0.014). Recovery from injury in wild-type mice was affected by hormone deficiency. Sham mice recovered preinjury isometric strength by 14 d (96% ± 2%), whereas Ovx mice maintained deficits at 14 and 21 d after injury (80% ± 3% and 84% ± 2%, P < 0.001). CONCLUSIONS: Ovarian hormone status did not affect the vulnerability of skeletal muscle to strength loss after eccentric contractions. However, ovarian hormone deficiency did impair the recovery of muscle strength in female mice.